so...as一般用于否定句和疑问句，而as...as一般用于肯定句。so as意为只要，用于否定句和疑问句，翻译成像…般那样。as...as意为和...一样，表示同级的比较。使用时要注意第一个as为副词，第二个as为连词。
扩展资料
He crept in so as not to disturb his sleeping parents.
他蹑手蹑脚地走进去，以免惊醒熟睡的父母。
She had put her hair up so as to look older.
她把头发盘起来以便让自己看起来更成熟些。
Services must be structured so as to avoid pitfalls.
服务业必须形成层次结构以免隐患。
The mother moved around softly so as not to disturb the sleeping child.
母亲轻手轻脚地走动，生怕惊动了熟睡的孩子。
I live here alone so as not to be disturbed by others.
我一个人住在这里，就是想耳根清净些。
